Calcium, an essential nutrient for bone health, is commonly found in dairy products as well as vitamins. Although calcium is an essential nutrient for bone health, past studies have linked calcium supplements to heart disease risk. The researchers, located at universities across the country, analyzed data from the large-scale Canadian Multicentre Osteoporosis Study (CaMos) seeking to determine whether calcium and vitamin D intake were associated with overall increased risk of death.

"We found that daily use of calcium supplements in women was associated with a lower risk of death, irrespective of cause," said the study's lead author, Prof. Goltzman, Director, Calcium Research Laboratory at McGill. "The benefit was seen for women who took doses of up to 1,000 mg per day, regardless of whether the supplement contained vitamin D."

The longitudinal study of participants living in or near 9 cities across Canada monitored the health of 9,033 Canadians between 1995 and 2007. During that period, 1,160 participants died. Although the data showed women who took calcium supplements had a lower mortality risk, there was no statistical benefit for men. The study found no conclusive evidence that vitamin D had an impact on mortality.

"Higher amounts of calcium were potentially linked to longer lifespans in women, regardless of the source of the calcium," says Goltzman. "In other words, the same benefits were seen when the calcium came from dairy foods, non-dairy foods or supplements."

This study was funded by the Canadian Institutes of Health Research and industry partners.